netfilter: nft_payload: fix C-VLAN offload support

- add another struct flow_dissector_key_vlan for C-VLAN
- update layer 3 dependency to allow to match on IPv4/IPv6

Fixes: 89d8fd44 ("netfilter: nft_payload: add C-VLAN offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

include/net/netfilter/nf_tables_offload.h

@@ -45,6 +45,7 @@ struct nft_flow_key {
 	struct flow_dissector_key_ports			tp;
 	struct flow_dissector_key_ip			ip;
 	struct flow_dissector_key_vlan			vlan;
+	struct flow_dissector_key_vlan			cvlan;
 	struct flow_dissector_key_eth_addrs		eth_addrs;
 	struct flow_dissector_key_meta			meta;
 } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */

net/netfilter/nft_payload.c

@@ -241,7 +241,7 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
+		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
 				  vlan_tci, sizeof(__be16), reg);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
@@ -249,8 +249,9 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
+		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
 				  vlan_tpid, sizeof(__be16), reg);
+		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 		break;
 	default:
 		return -EOPNOTSUPP;